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The purpose of this paper is to conduct a comparative study of the surface modifications induced by two different lasers on a 2050‐T8 aluminum alloy, with a specific consideration of residual stress and work‐hardening levels.

Two lasers have been used for Laser shock peening (LSP) treatment in water‐confined regime: a Continuum Powerlite Plus laser, operating at 0.532 mm with 9 ns laser pulses, and near 1.5mm spot diameters; a new generation Gaia‐R Thales laser delivering 10 J‐10 ns impacts, with 4‐6mm homogeneous laser spots at 1.06 mm. Surface deformation, work‐hardening levels and residual stresses were analyzed for both LSP conditions. Residual stresses were compared with numerical simulations using a 3D finite element (FE) model, starting with the validation of surface deformations induced by a single laser impact.

Similar surface deformations and work‐hardening levels, but relatively lower residual stresses were obtained with the new large 4‐6 mm impact configuration. This was attributed to a reduced number of local cyclic loadings (2) compared with the small impact configuration (4). Additionally, more anisotropic stresses were obtained with small impacts. FE simulations using Johnson‐Cook's material' behavior were shown to simulate accurately surface deformations, but to overestimate maximum stress levels.

This work should provide LSP workers a better understanding of the possible benefits from the different LSP configurations currently co‐existing: using small (<2 mm) impacts at high‐cadency rates or large ones (>4‐5 mm). Moreover, experimental results and simulated data had never been presented on 2050‐T8 Al alloy.

An experimental (and numerical) comparison using two distinct laser sources for LSP, has never been presented before. This preliminary work should help LSP workers to choose adequate sources.

The purpose of this paper is to present an original study of industrial inductors with different air-gap materials in order to reduce the vibration and noise of inductors. Acoustic comfort is an increasingly important factor at the design stage of industrial inductors associated to converters. In addition, power converters in the railway domain are more and more compact and powerful.

Experiments, simulations and test devices were used to determine the main physical phenomena that generate the undesirable audible noise. Electric and vibratory measurements (modal and operational analysis) were compared with the numerical calculations. PWM and sinusoidal supply were taken into account and different prototypes with different materials in the air-gap were built.

This study analyzes and details the origin of the electromagnetic noise due to the vertical mode, in order to reduce the vibration and noise of inductors. A detailed analysis using finite element simulation and experimental measurements of free-free mode or forced mode under electrical excitation was conducted to interpret the vibrations of the structure. In addition, in order to observe trends and the impact of magnetostriction effect, the authors propose a simplified model.

Electric and vibratory measurements (modal and operational analysis) are compared with the numerical calculations.

This paper gives a response about the origin of the noise with different experimental measurements. Changing the air-gap material is beneficial for the deflection of the inductor. However, it has been presented that, following the shape of the inductor, it is beneficial to reduce or increase the stiffness of the material depending on the column height. For a fixed Young’s modulus air-gap, a ratio Column height/air-gap thickness exists, which makes it possible to cancel the deflection.